Retarding chamber



June 18, 1929.

L. A. GRIMES RETARDJENG CHAMBER Filed June 25. 1925 INVENTOB Zesfen -G/"//775 If BY A SQ 17- ATTORNEY Patented June 18, 1929.

UNITED STATES PATENT OFFICE.

LESTER A. GRIMES, OF MONTCLAIR, NET/V JERSEY, ASSIGNOR T0 GRIMES SPRINKLER COMPANY, INC., OF NEWARK, NEW JERSEY, A CORPORATION OF NEW JERSEY.

RETARDING CHAMBER.

Application filed June 25, 1925. Serial No. 39,434.

The present invention relates to retarding chambers for use in connection with automatic sprinkler systems of the type wherein a normally closed check valve controls the flow from the water supply to the sprinkler heads. In such systems the opening of one or more sprinkler heads, by fire or accident, relieves the pressure beyond the valve, whereupon the valve is unseated by pressure in the water main and a flow established through the valve to the opened head. In connection with the check valve is a normally closed auxiliary valve which controls the flow through a passage leading from the water main to a retarding chamber in combination with one or more alarm devices.

The check valve and the auxiliary valve are so arranged that opening and closing" movements of the latter are wholly dependent upon and controlled by like movements of the former. Because of varying pressure in the main, the check valve is subject to water hammer and" is thereby intermittently unseated to some extent. If the auxiliary valve is also unseated, by such movements of the main valve, there will be a flow to the retarding chamber; and, unless otherwise cared for, suflicient water might bank up in the latter to actuate the alarm.

The object of the invention is the provi sion of means for controlling the banking up of water in the retarding chamber so that such intermittent flow, occasioned as by water hammer, or even a more constant seepage through the valves, will not be effective to give a false alarm; and, at the same time, means whereby any continuous flow, occasioned as by the opening of a sprinkler head, will promptly be effective to give an alarm.

More specifically the invention is a valve operable under normal conditions by gravity to maintain the retarding chamber open and thereby prevent the banking up of water, and operable by a continuous flow to close the chamber in order that water may bank up therein to sound an alarm.

For the purpose of illustration, a preferred embodiment of the invention is shown in the accompanying drawings; but it is to be understood that such showing is not to be taken'as defining the limits of the invention, reference being had to the appended claims for that purpose.

In the drawings- Fig. 1 is a vertical section of the device as a whole; and

Fig. 2 is a vertical section on line 2-2 of Fig. 1 showing the valve in elevation. The casing A of the retarding chamber 1s provided at its bottom with the inlet B which communicates with the usual alarm check valve. At the top of the casing is the outlet C to any. preferred type of circuit closer embodying a diaphragm displaceable by water pressure to close the contacts of an electrical alarm. A second outlet D leads to any suitable type of water rotary for actuating a mechanical alarm. The space E within the casing is ordinarily re ferred to as the accumulation chamber.

A drain pipe F for the accumulation chamber is screwed into a threaded opening G 111 the side of the casing. A continuation F of the drain pipe may be cast integral with the casing, as shown; or, if preferred, the pipe F may itself be extended 1nto the chamber, and the cast portion F dispensed with. The lower side of the drain is provided with a threaded opening I into which is screwed the nipple J having therethrough a passage K, which passage affords communication between the accumulation chamber and the drain. The valve L is preferably a block of metal, circular in cross-section, having arms or uprights M to the top of which is secured a ring N which surrounds the lower portion of the nipple. This valve with its side arms and ring is preferably formed from a single piece, or cast integrally. One or more pins 01' stops 0 project from the nipple beneath the ring and limit the downward movement of the valve. The lower end of the nipple J forms a seat for the valve L; and, when seated, the valve closes the passage K and thus cuts off communication between the chamber E and the drain.

Preferably the arrangement and positioning of the parts is such that the opening I will be aligned with the inlet 13, the passage K co-axial with the inlet passage, and the valve L concentric with both passages and in the direct line of flow from the inlet.

In operation, the valve L is of a mass or weighted to the point where the pressure on its lower side of a small flow from the alarm valve, occasioned by seepage or slight Water hammer, will be insufficient to raise the valve to close the passage K; and the drain, being thus left open, will carry off such flow. When the water hammer exerts a force sufficient to open the alarm valve to such an extent that the pressure of the flow therefrom will raise the valve L, and thus close the drain, water will bank up in the accumulation chamber so long as such flow continues; but the capacity of the accumulation chamber is so proportioned'to the duration of such water hammer and consequent continuance of flow that the chamber will not become filled before the flow ceases,-therefore neither the electrical nor mechanical alarm will be set in operation. Upon cessation or diminution of such flow the valve L will drop from its seat by gravity, thus opening'the drain, and the accumulated water will be carried off.

Upon the opening of one or more sprinkler heads, in the event of fire, both the main check valve and the auxiliary Valve are opened, and a continuous flow to the retarding chamber takes place. The pressure of such fiowon the valve L will be suflicient to raise and hold it to its seat, thus closing the passage K; water will then bank up in the accumulation chamber, and when the chamber is filled the alarm devices will be set in operation.

Having thus described the invention, the following is claimed:

1. In a retarding device for an automatic sprinkler system, a casing having inlet and outlet openings, an accumulation chamber, a drain pipe, a passage between said pipe and the accumulation chamber, and a valve carried by said pipe operable under normal conditions by gravity to maintain said pas- V sage open and operable by a continuous flow beyond a predetermined amount through the inlet to close said passage.

2. In a retarding chamber for an automatic sprinkler system, a casing having inlet and outlet openings, a drain pipe within said casing positioned at a right angle to the axis of the inlet, means for controlling said drain pipe comprising a nipple having a passage-way coaxial with the said inlet, and a valve supported by said nipple o zerable by a continuous flow through the inlet to close said passage and operable by gravity upon cessation of. flow to open said passage.

3. In a retarding chamber for an automatic sprinkler system, a casing having inlet and outlet openings, a drain pipe within said casing positioned at a right angle to the axis of the inlet, a valve forcontrolling said drain comprising a nipple having a pas sage therethrough coaxial with said inlet and a closure for said passage carried by the nipple and positioned in the path of flow from the inlet whereby flow beyond a predetermined amount will raise said closure to cut off said passage.

In testimony whereof, I have signed my name to this specification.

LESTER A. GRIMES. 

